code: def test_diff_old_deleted():
      td = diff_table(
          {"metric.json": {"a.b.d": {"old": "old", "new": None}}},
          title="Metric",
      )
      assert td.as_dict() == [
          {
              "Path": "metric.json",
              "Metric": "a.b.d",
              "HEAD": "old",
              "workspace": "-",
              "Change": "-",
          }
      ]
  
imports: import textwrap
  import pytest
  from dvc.compare import diff_table, metrics_table, show_diff, show_metrics
  from dvc.utils.serialize import YAMLFileCorruptedError
label_desc: Use image node_id 9 for calling a global function with example usage: test_diff_old_deleted() without return types